Editing Encyclopedia:Image use policy (section)

===Format<span id="image formats"></span>===
{{anchor|FORMAT}}{{shortcut|WP:IUP#FORMAT}}
{{Further|Wikipedia:Preparing images for upload}}
Generally:
* Drawings, [[Icon (computing)|icons]], [[logo]]s, maps, flags and other such images are preferably uploaded in [[Scalable Vector Graphics|SVG]] [[Image file formats|format]] as [[vector images]]. Images with large, simple, and continuous blocks of color which are not available as SVG should be in [[Portable Network Graphics|PNG]] format.
* Software [[screenshot]]s should be in [[Portable Network Graphics|PNG]] format.
* Photos and [[Image scanner|scanned]] images should be in [[JPEG]] format, though a [[Portable Network Graphics|PNG]] may be useful as well for simple subjects (where PNG would result in a smaller file without degrading quality).
* TV- and movie screenshots should be in [[JPEG]] format.
* Inline animations should be in animated [[GIF]] format.
* Video should be in [[Ogg]]/[[Theora]] or [[WebM]] format.

Generally speaking, you should not contribute images consisting solely of formatted or unformatted text, tables, or mathematical formulas.  In most cases these can instead be typed directly into an article in [[Help:Wiki markup|wiki markup]] (possibly using MediaWiki's special syntax for [[Help:Table|tables]], [[Help:Displaying a formula|math]]).  This will make the information easier to edit, as well as make it [[web accessibility|accessible]] to users of screen readers and text-based [[web browser|browsers]].

In general, if you have a good image that is in the wrong format, convert it to the correct format before uploading. However, if you find a map, flag, etc. in JPEG format, only convert it to PNG if this reduces the file size. For further advice on converting JPEG to PNG, see [[Wikipedia:How to reduce colors for saving a JPEG as PNG]].

Most of the maps on the [[CIA World Factbook]] website were coded as JPEG, but are now coded as GIF. To update these photos, download the GIF picture from the CIA Factbook, convert it into a PNG, and upload it to Wikipedia.

Try to avoid editing JPEGs too frequently—each edit creates more loss of quality. If you can find an original of a photograph in 16-bit or 24-bit PNG or [[TIFF]], edit that, and save as JPEG before you upload. A limited variety of edits (crops, rotation, flips) can be performed [[lossless]]ly using [http://jpegclub.org/ jpegcrop] (Windows) or [http://jpegclub.org/jpegtran/ jpegtran]  (other); try to use this where possible.

JPEG files should not use [[arithmetic coding]] due to limited browser support. Please prefer [[Huffman coding]] for JPEG files instead.

Avoid images that mix photographic and iconic content.
Though [[Cascading Style Sheets|CSS]] makes it easy to use a PNG overlay on top of a JPEG image, the Wikipedia software does not allow such a technique. Thus, both parts must be in the same file, and either the quality of one part will suffer, or the file size will be unnecessarily large.

SVG support is implemented as of September 2005 (see [[meta:SVG image support]]). The SVG is not directly given to the browser; instead, the SVG file is dynamically rendered as a PNG at a given size, and that PNG is given to the browser.

====Images containing text<span id="no text"></span>====
If you create an image that contains text, please also upload a version without any text. It will help Wikipedians translate your image into other languages.

SVG images can contain text in multiple languages in a single file (using a <code>switch</code> element). See {{section link|Commons:Help:Translation tutorial#SVG files}}.

====Cropping<span id="edit for relevancy"></span>====
Within reason, crop an image to remove irrelevant areas. But do not "throw away information"; for example, if a photograph shows George Washington and Abraham Lincoln together at a birthday party, and the article you're working on requires only Lincoln, consider uploading ''both'' the original image and the crop of Lincoln. Also, if an image has captions as an inherent part of the artwork (as with book illustrations, early cartoons, many lithographs, etc.), don't crop them, or upload the original uncropped version as well.<!--probably should say something about retouching as well, but I'm out of energy-->

====Animated images====
{{anchor|ANIM}}{{shortcut|WP:IUP#ANIM}}
It may be preferable to convert a long or color-rich animation to [[Ogg]]/[[Theora]] format instead of GIF. Ogg does not allow an animation to play automatically on page loading, but it can contain audio and has generally better resolution.

Inline animations should be used sparingly; a static image with a link to the animation is preferred unless the animation has a very small file size. Keep in mind the problems with print compatibility mentioned elsewhere on this page.<!--where?-->

====Uploaded image size<span id="high-res"></span>====
{{Shortcut|WP:FILESIZE}}
{{redirect|WP:FILESIZE|text=You may be looking for [[#Displayed image size|Displayed image size]], another section on this page}}
Wikipedia and its sister projects are repositories of knowledge, so images should be uploaded at high resolution whether or not this seems "necessary" for the use immediately contemplated{{mdashb}}"saving server space" is ''not'' a valid consideration in general, though there is a 1,000{{nbsp}}MB (1{{nbsp}}GB) limit.
Exception: If the image is [[WP:NFCC|copyrighted]] and used under fair use, the uploaded image must be as low-resolution as possible consistent with its fair-use rationale, to prevent use of Wikipedia's copy as a substitute for the original work.

The servers automatically handle the scaling of images (whatever their original size) to the sizes called for in particular articles, so it is neither necessary nor desirable to upload separate reduced-size or reduced-quality "thumbnail" versions, although compressing [[Portable Network Graphics|PNGs]] may be useful.